US4744804A - Dust pre-removal method in a dry moving bed type adsorption tower - Google Patents

Dust pre-removal method in a dry moving bed type adsorption tower Download PDF

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Publication number
US4744804A
US4744804A US07/006,247 US624787A US4744804A US 4744804 A US4744804 A US 4744804A US 624787 A US624787 A US 624787A US 4744804 A US4744804 A US 4744804A
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United States
Prior art keywords
dust
granular adsorbent
pipe
adsorption tower
gas
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Expired - Fee Related
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US07/006,247
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English (en)
Inventor
Kuninori Furuyama
Yoshiro Ito
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Mitsui Miike Engineering Corp
Mitsui Mining Co Ltd
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Mitsui Miike Engineering Corp
Mitsui Mining Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • B01D53/06—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with moving adsorbents, e.g. rotating beds
    • B01D53/08—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with moving adsorbents, e.g. rotating beds according to the "moving bed" method
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2253/00—Adsorbents used in seperation treatment of gases and vapours
    • B01D2253/10—Inorganic adsorbents
    • B01D2253/102—Carbon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/302—Sulfur oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/40—Nitrogen compounds
    • B01D2257/404—Nitrogen oxides other than dinitrogen oxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2259/00—Type of treatment
    • B01D2259/40—Further details for adsorption processes and devices
    • B01D2259/40007—Controlling pressure or temperature swing adsorption
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2259/00—Type of treatment
    • B01D2259/40—Further details for adsorption processes and devices
    • B01D2259/40083—Regeneration of adsorbents in processes other than pressure or temperature swing adsorption
    • B01D2259/40088—Regeneration of adsorbents in processes other than pressure or temperature swing adsorption by heating

Definitions

  • This invention relates to a dust pre-removal method in a dry moving bed type adsorption tower and more particularly, it is concerned with a method of reducing the dust concentration in a gas passing through a granular material bed in an apparatus for contacting a gas with a granular material, e.g. a dry moving bed type adsorption tower used for removal of SO x and NO x from waste gases.
  • Waste gas 1 from boilers, etc. is introduced into adsorption tower 2, brought into contact with a granular carbonaceous adsorbent 3 packed and held in the tower, thus subjected to reactions for removal of SO x and NO x and to removal of dust and exhausted through a stack (not shown) in the air.
  • carbonaceous adsorbent 3 is continuously withdrawn from the lower part of adsorption tower 2 by feeder 5 while holding a constant level of powder in hopper 4 over the upper part of adsorption tower 2 and thus forming a moving bed in adsorption tower 2, and SO 2 in the gas is adsorbed in the form of H 2 SO 4 during the course of entering and leaving adsorption tower 2, while dusts and the like are also adsorbed.
  • the adsorbent withdrawn from feeder 5 is then fed to hopper 7 for regeneration tower 8 by means of bucket conveyor 6, introduced into regeneration tower 8 while holding a constant level of powder in hopper 7 and continuously withdrawn therefrom by feeder 9.
  • the adsorbent is heated to decompose H 2 SO 4 adsorbed into SO 2 and thus released SO 2 gas 13 is fed to another plant for byproducts (not shown).
  • the adsorbent withdrawn by feeder 9 is subjected to vibrating screen 10 where dusts in the waste gas and abrasive powders formed during movement, adhered to the adsorbent, are separated, and then returned to hopper 4 by means of bucket conveyor 11. Since the quantity of the adsorbent decreases due to the chemical reactions in regeneration tower 8, the withdrawal from vibrating screen 10 and the entrainment with the gas, the decreased adsorbent should be made up from make-up hopper 12.
  • a waste gas from a boiler or the like is ordinarily supplied to an adsorbing tower via a dust collector, but generally has a dust concentration of about 200-400 mg/Nm 3 .
  • the dust removal or dedusting capacity of an adsorption tower is generally so large that in a test of flowing a gas at a linear velocity of 0.15 Nm/sec through a moving bed with a thickness of 1.5 m using an adsorbent with a mean grain size of about 10 mm, for example, at the outlet of the adsorption tower, there is little dust having the same composition as that at the inlet thereof.
  • the dust concentration itself at the outlet of an adsorption tower is not so small, the most part of which consists of a fine powder of carbonaceous adsorbent. Since the dust concentration of a waste gas exhausted in the air has severely been regulated independently of the dust composition, it is required, in order to overcome this regulation, to provide a dust collector even at the rear of an adsorption tower in many cases.
  • a fine powder of an adsorbent contained in an outlet gas of an adsorption tower is produced by abrasion and cracking due to collision of the grains each other at various positions in the cycle line of the adsorbent.
  • sieving is carried out by installing a vibrating screen, but it is difficult to sufficiently remove a fine powder of about several microns by an ordinary vibrating screen and a large part of the fine powder passes with larger grains.
  • a fine powder can well be removed by rinsing out with a gas and accordingly, the powder rinsed and removed in an adsorption tower results in increase of the dust concentration at the outlet of the adsorption tower.
  • a dust collector When the dust concentration in a waste gas is not less than the regulation value at the outlet of an adsorption tower, a dust collector must be installed, the size of which is dependent upon the quantity of a waste gas to be processed and in general, substantially similar to that of the adsorption tower. Such a dust collector not only occupies a large space, but also presents large costs for installation and maintenance.
  • FIGS. 2(a) and (b) are schematic views of flow diagram showing a comparison and one embodiment for practicing the dust pre-removal method according to the present invention respectively.
  • FIG. 3 is a schematic view of a dry moving bed type adsorber for practicing a fundamental experiment relating to the present invention.
  • FIG. 4 is a graph showing the relationship between the gas flow rate and dust concentration resulting from the fundamental experiment.
  • FIG. 5 is a schematic view of an adsorption tower of dry moving bed and two-tower type for practicing a fundamental experiment relating to the present invention.
  • FIGS. 6(a) and (b) are schematic views of adsorption towers showing other embodiments of the present invention.
  • the present invention provides a dust pre-removal method in an adsorption tower of the dry moving bed type using a granular adsorbent such as granular carbonaceous adsorbent, characterized by previously subjecting the granular adsorbent entering the adsorption tower to rinsing with a gas in a feed pipe for the adsorbent.
  • a granular adsorbent such as granular carbonaceous adsorbent
  • the gas from the adsorption tower as the above described rinsing gas in a proportion of 0.1 to 5 vol %, preferably 0.3 to 2 vol %, more preferably 0.5 to 0.8 vol. % to the whole volume of the gas to be processed in the tower.
  • Hopper 4 and adsorption tower 2 are ordinarily connected by a pipe with an inner diameter of about 150 to 300 mm and a granular adsorbent is moved downward continuously under a packed state in this connection pipe.
  • the inside of adsorption tower 2 is generally held at a pressure of several ten to several hundred mmHg. If a hole is made in the connection pipe, therefore, the gas in the adsorption tower is passed through the connection pipe and discharged in the air from the hole, while during the same time, the adsorbent grains and gas are contacted in the connection pipe to effect rinsing and removing of a fine powder.
  • the principle is as described above, but in practice, the discharge of a gas with a high dust concentration in the air is not permitted by the regulation and it is further required to operate the system in stable manner.
  • FIG. 2(b) The above described principle of the present invention can be realized, for example, by the use of a system as shown in FIG. 2(b) comprising waste gas 1 from a boiler, etc., adsorption tower 2, granular carbonaceous adsorbent 3, hopper 4, dust removal pipe 14, small-sized dust collector 15, fan 16 and discharge regulator 17.
  • the gas in adsorption tower 2 is sucked by fan 16, moved upward in contact with the adsorbent grains in dust removal pipe 14 and fed to small-sized dust collector 15 with fine powder, where the fine powder is removed.
  • the thus rinsed gas is compressed by fan 16 and then added to waste gas 1 from a boiler, etc. at the inlet of adsorption tower 2.
  • the flow rate of the gas rising in dust removal pipe 14 must so be controlled that the adsorbent grains moving downward be not fluidized.
  • the dust collector and fan may each be of a small size.
  • the capacity thereof is generally about 100 Nm 3 /h for a connection pipe with a diameter of 200 mm.
  • the dust concentration rises rapidly at a flow rate of higher than a certain value and in particular, the dust concentration changes rapidly with a slight change of flow rate.
  • the dust in AC layer consists mainly of a powder with a grain size of larger than a certain value and the dust concentration thus changes rapidly at the flow rate capable of blowing such a powder off.
  • Example 2 A similar experiment to that of Example 2 was carried out using an apparatus as shown in FIG. 5 and the dust concentrations were measured at points A, B and C. All dust concentrations mg/Nm 3 at these points are shown in Table 2 (average values of measurements of 6 times):
  • Example 3 A similar experiment to that of Example 3 was carried out using an apparatus as shown in FIG. 6(a) and the dust concentrations were measured at Points A, B, C and D. All dust concentrations mg/Nm 3 at these points are shown in Table 3 (gas flow rate: 1000 Nm 3 /h):
  • the dust concentration at Point D has a higher value, i.e. 125 mg/Nm 3 as the converted value at 1000 Nm 3 /h. This is due to that AC contains a very large quantity of fine powder to be removed at the inlet of Tower II, which will increase the dust concentration at Point C unless removed, and the fine powder is effectively removed according to the present invention.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Treating Waste Gases (AREA)
  • Separation Of Gases By Adsorption (AREA)
US07/006,247 1984-02-16 1987-01-09 Dust pre-removal method in a dry moving bed type adsorption tower Expired - Fee Related US4744804A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP59-26154 1984-02-16
JP59026154A JPS60172330A (ja) 1984-02-16 1984-02-16 乾式移動層式吸着塔におけるプレ脱塵方法

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US06896587 Continuation 1986-08-18

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Country Status (5)

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US (1) US4744804A (enrdf_load_stackoverflow)
EP (1) EP0161741B1 (enrdf_load_stackoverflow)
JP (1) JPS60172330A (enrdf_load_stackoverflow)
CA (1) CA1260406A (enrdf_load_stackoverflow)
DE (1) DE3580299D1 (enrdf_load_stackoverflow)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4960447A (en) * 1986-11-12 1990-10-02 Bergwerksverband Gmbh Reactor with moving layer for the removal of undesirable gaseous components from gases
US5344616A (en) * 1988-12-30 1994-09-06 Steag Aktiengessllschaft Apparatus for the separation of undesirable constituents from a waste gas
US5405812A (en) * 1990-08-17 1995-04-11 Steag Aktiengesellschaft Method and arrangement for purifying a carbon-containing adsorption medium
US5494500A (en) * 1990-11-26 1996-02-27 The Social Welfare Foundation Hokkaido Rehabily Activated carbon, production thereof and adsorption using activated carbon
US20040226450A1 (en) * 2002-11-08 2004-11-18 Chemical Recovery International, Inc. Moving bed adsorber/desorber and low flow (high yield) desorber devices and their methods of use
US20050028672A1 (en) * 2003-08-07 2005-02-10 Hickerson Steven A. Apparatus and process for removing contaminants from a flowing gas stream
US20080196365A1 (en) * 2007-02-20 2008-08-21 Atomic Energy Council - Institute Of Nuclear Energy Research Adjustable dual-blade dust filter using granular bed flow
US20080202338A1 (en) * 2007-02-23 2008-08-28 Tw Environmental, Inc. System and method for a moving bed adsorber for contaminant removal
CN101785953A (zh) * 2010-03-19 2010-07-28 东南大学 利用错流移动床去除水泥窑炉烟气中有害成分的装置及方法
US20110315016A1 (en) * 2009-03-16 2011-12-29 J-Power Entech, Inc. Dry exhaust-gas treating apparatus
US20110315017A1 (en) * 2009-03-16 2011-12-29 J-POWER En Tech, Inc. Regeneration tower and dry apparatus for exhaust-gas treatment
WO2023050895A1 (zh) * 2021-09-28 2023-04-06 中国华能集团清洁能源技术研究院有限公司 用于钢厂烧结机烟气的低温脱硫脱硝系统

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3609164A1 (de) * 1986-03-19 1987-10-01 Uhde Gmbh Vorrichtung zur feststoffseitigen kopplung von wanderbettadsorptionsvorrichtungen
WO1988006482A1 (en) * 1987-02-27 1988-09-07 Tri-Dim Filter Corporation Air cleaning system
CN103968675B (zh) * 2014-05-20 2015-07-08 莱芜钢铁集团有限公司 一种转底炉低温烟气预除尘装置与预除尘方法

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE352081C (de) * 1920-06-05 1922-04-21 Hermann Klug Verfahren und Einrichtung zur Reinigung und Umlagerung der Fuellkoerper eines Wanderschichtfilters zur Reinigung von Luft oder Gasen
US2493218A (en) * 1945-12-04 1950-01-03 Socony Vacuum Oil Co Inc Gas-solid contact process
US2673832A (en) * 1949-11-01 1954-03-30 Sun Oil Co Elevation of subdivided solids
US2992065A (en) * 1958-07-31 1961-07-11 Reinluft G M B H Process for removing sulfur oxides from gases
US3067131A (en) * 1961-03-27 1962-12-04 Socony Mobil Oil Co Inc Periodic introduction of granular contact material into high pressure vessel
US3760565A (en) * 1971-07-19 1973-09-25 Aluminum Co Of America Anti-pollution method
US3960529A (en) * 1970-10-16 1976-06-01 Bergwerksverband Gmbh Apparatus for removing sulfur oxide from exhaust gases
US4017278A (en) * 1974-09-30 1977-04-12 Combustion Power Company, Inc. Method and apparatus for removing finely divided solids from gas
US4083701A (en) * 1975-10-09 1978-04-11 Deutsche Babcock Aktiengesellschaft Process and apparatus for removing undesirable gases from flue gases
US4203736A (en) * 1976-05-06 1980-05-20 Gimag Aktiengesellschaft Method and apparatus for purifying a gas of suspended particles
US4292054A (en) * 1978-10-06 1981-09-29 Deutsche Babcock Aktiengesellschaft Apparatus for monitoring the temperature of adsorbers
US4306886A (en) * 1978-12-01 1981-12-22 Berg Clyde Multiple stage high temperature stripping zone in a hypersorption process

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE352081C (de) * 1920-06-05 1922-04-21 Hermann Klug Verfahren und Einrichtung zur Reinigung und Umlagerung der Fuellkoerper eines Wanderschichtfilters zur Reinigung von Luft oder Gasen
US2493218A (en) * 1945-12-04 1950-01-03 Socony Vacuum Oil Co Inc Gas-solid contact process
US2673832A (en) * 1949-11-01 1954-03-30 Sun Oil Co Elevation of subdivided solids
US2992065A (en) * 1958-07-31 1961-07-11 Reinluft G M B H Process for removing sulfur oxides from gases
US3067131A (en) * 1961-03-27 1962-12-04 Socony Mobil Oil Co Inc Periodic introduction of granular contact material into high pressure vessel
US3960529A (en) * 1970-10-16 1976-06-01 Bergwerksverband Gmbh Apparatus for removing sulfur oxide from exhaust gases
US3760565A (en) * 1971-07-19 1973-09-25 Aluminum Co Of America Anti-pollution method
US4017278A (en) * 1974-09-30 1977-04-12 Combustion Power Company, Inc. Method and apparatus for removing finely divided solids from gas
US4083701A (en) * 1975-10-09 1978-04-11 Deutsche Babcock Aktiengesellschaft Process and apparatus for removing undesirable gases from flue gases
US4203736A (en) * 1976-05-06 1980-05-20 Gimag Aktiengesellschaft Method and apparatus for purifying a gas of suspended particles
US4292054A (en) * 1978-10-06 1981-09-29 Deutsche Babcock Aktiengesellschaft Apparatus for monitoring the temperature of adsorbers
US4306886A (en) * 1978-12-01 1981-12-22 Berg Clyde Multiple stage high temperature stripping zone in a hypersorption process

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4960447A (en) * 1986-11-12 1990-10-02 Bergwerksverband Gmbh Reactor with moving layer for the removal of undesirable gaseous components from gases
US5344616A (en) * 1988-12-30 1994-09-06 Steag Aktiengessllschaft Apparatus for the separation of undesirable constituents from a waste gas
US5405812A (en) * 1990-08-17 1995-04-11 Steag Aktiengesellschaft Method and arrangement for purifying a carbon-containing adsorption medium
US5494500A (en) * 1990-11-26 1996-02-27 The Social Welfare Foundation Hokkaido Rehabily Activated carbon, production thereof and adsorption using activated carbon
US5620506A (en) * 1990-11-26 1997-04-15 The Social Welfare Foundation Hokkaido Rehabily Activated carbon, production thereof and adsorption using activated carbon
US20040226450A1 (en) * 2002-11-08 2004-11-18 Chemical Recovery International, Inc. Moving bed adsorber/desorber and low flow (high yield) desorber devices and their methods of use
US7309379B2 (en) * 2002-11-08 2007-12-18 Tw Environmental, Inc. Moving bed adsorber/desorber and low flow (high yield) desorber devices and their methods of use
US20050028672A1 (en) * 2003-08-07 2005-02-10 Hickerson Steven A. Apparatus and process for removing contaminants from a flowing gas stream
US7014682B2 (en) * 2003-08-07 2006-03-21 Hickerson Steven A Apparatus and process for removing contaminants from a flowing gas stream
US7727298B2 (en) * 2007-02-20 2010-06-01 Atomic Energy Council Adjustable dual-blade dust filter using granular bed flow
US20080196365A1 (en) * 2007-02-20 2008-08-21 Atomic Energy Council - Institute Of Nuclear Energy Research Adjustable dual-blade dust filter using granular bed flow
US20080202338A1 (en) * 2007-02-23 2008-08-28 Tw Environmental, Inc. System and method for a moving bed adsorber for contaminant removal
US7871460B2 (en) 2007-02-23 2011-01-18 Tw Environmental, Inc. System and method for a moving bed adsorber for contaminant removal
US20110315016A1 (en) * 2009-03-16 2011-12-29 J-Power Entech, Inc. Dry exhaust-gas treating apparatus
US20110315017A1 (en) * 2009-03-16 2011-12-29 J-POWER En Tech, Inc. Regeneration tower and dry apparatus for exhaust-gas treatment
US8500888B2 (en) * 2009-03-16 2013-08-06 J-Power Entech, Inc. Regeneration tower and dry apparatus for exhaust-gas treatment
US8518165B2 (en) * 2009-03-16 2013-08-27 J—Power Entech, Inc. Dry exhaust-gas treating apparatus
CN101785953A (zh) * 2010-03-19 2010-07-28 东南大学 利用错流移动床去除水泥窑炉烟气中有害成分的装置及方法
CN101785953B (zh) * 2010-03-19 2012-02-22 东南大学 利用错流移动床去除水泥窑炉烟气中有害成分的装置及方法
WO2023050895A1 (zh) * 2021-09-28 2023-04-06 中国华能集团清洁能源技术研究院有限公司 用于钢厂烧结机烟气的低温脱硫脱硝系统

Also Published As

Publication number Publication date
EP0161741A1 (en) 1985-11-21
CA1260406A (en) 1989-09-26
JPH0432687B2 (enrdf_load_stackoverflow) 1992-06-01
JPS60172330A (ja) 1985-09-05
EP0161741B1 (en) 1990-10-31
DE3580299D1 (de) 1990-12-06

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